Fix A Plugged Air Conditioner Drain Line

When the drain line on your central HVAC system is clogged, the internal unit will soon begin to leak water that has condensed on the coil and collected in the drain pan with nowhere to go.
That leaking moisture can quickly damage flooring and can cause wall stains. It might also cause mold and rot as well.
Getting the issue fixed immediately is of the utmost importance.
If you’re handy and know where to find the drain, you can attempt this repair yourself; otherwise, make a call to your heating and air conditioning (HVAC) professional.
A skilled handyman might be able to clear an AC drain line too. While waiting for the AC drain line repair, shut off the system to prevent any more condensate from being produced.

Air Conditioner Drain Line Repair Tips

You get the basics here including tips for unclogging the internal unit of your central air conditioning system, if you want to attempt the repair yourself. In addition, you’ll find repair costs for calling a professional HVAC technician or a handyman. Finally, there are several links below that give you further information about making this repair and what it involves. Our goal in this repair guide is always to help you decide whether to call a professional for the house repair or to give it a shot yourself. In this situation, trying to clear the drain won’t hurt the unit if you’re careful, and it might save you a sizable repair bill.

The process isn’t complicated. Part of your HVAC system is known as an evaporator coil or indoor coil.
It is housed inside the furnace or air handler or on top of it. The coil gets very cold when refrigerant travels through it and collects heat from your house.
As indoor air passes over the coil, not only is heat removed from it but some of the moisture from the air condenses onto the cold coil. The resulting water then runs into a drain pan.
The pan has a hose attached that typically runs to a drain in the floor. When the drain is clogged, the condensed water will leak, plain and simple.

Here’s what clearing the AC drain involves along with tips for repairing the problem:

Removing the sheet metal housing to the coil and pan

Locating the pan and drain

Inspecting the drain, and removing any obvious obstacles

Using a wet/dry vacuum like a Shop-Vac to vacuum sludge out of the drain line

The drain may empty outside near the air conditioner system’s condensing unit. If there’s a PVC pipe there, that’s what you want to vacuum out

Make the connection between the vacuum hose and the drain as airtight as possible to get the most from the vacuum power

If you can’t get to the drain end, you may have to cut the PVC drain pipe, clear it, and then put it back together with a connector and PVC glue

Let the vacuum run for several minutes, and then check the canister for sludge and water which may contain algae, mold and other things common to standing water

Alternate methods include using an air compressor to blow out the blockage or a plumber’s snake to clear it

Check the drain by pouring a cup of water into it to see/hear if it drains

Anti-algae tablets can be placed in the drain pain as a preventative, but make sure they don’t block the drain

Drain Line Repair Costs

How much does it cost to unclog an HVAC drain line? It depends on whether you do it yourself or call a pro. DIY repair costs will vary based on what you have to purchase for the job.

DIY Drain Line Repair Costs: If you have a wet vacuum and don’t have to cut any pipe, this repair might be free! Here are costs for items you might need to purchase:

Small wet/dry vacuum: $30 to $50 depending on capacity

Hack saw: $7 to $20 depending on quality

PVC pipe coupling: $2 to $4

PVC glue: $4 to $6

Drain snake: $10-$50 depending on length and quality

Air Compressor: $75 and up, depending on the quality and PSI pressure

Professional Drain Line Repair Costs: Most professional HVAC technicians charge more than $100 for this repair, often as high as $200 or more when the job is complex. As you can see, even if you have to buy some of the equipment, you’ll come out ahead if you can successfully make the repair yourself.

Ways to Lover HVAC Drain Repair Costs

Borrowing the tools required is the best way to save money on DIY air conditioner drain repair. If you decide to hire someone, consider calling a few handymen to get quotes, to see if they have experience unclogging drain lines and what they charge.

Additional Resources for AC Drain Clearing

These links provide you with additional information we think you’ll find very helpful.

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